Which devices can load the mode 4 codes into the IFF interrogator?

The correct answer is that all of the devices mentioned can load the mode 4 codes into the IFF interrogator. Mode 4 codes are essential for the identification of friendly aircraft and are part of the Identification Friend or Foe (IFF) system, which helps prevent friendly fire incidents.

The SKL (Simple Key Loader) and KYK-13 are devices used to load and manage secure communication keys, including mode 4 codes, into the IFF interrogators. The ANCD (Automatic Non-Classified Data Transfer Device) and KOI 8 are also designed for similar purposes, providing secure data transfer capabilities to load necessary codes.

Furthermore, the KY-57 and STU-III are secure voice communication devices that can handle mission critical data and secure key loading. Their ability to load mode 4 codes into IFF systems underscores their role in ensuring that the identification systems are accurately updated and operational.

Thus, the inclusion of all these devices indicates a comprehensive understanding of the equipment used in the IFF interrogation process and the versatility required in implementing secure communication measures. Each of these devices is integral in the operational readiness of air defense systems, reinforcing the importance of secure and precise communication.